1. Field of the Invention
The invention relates to a cable terminal or joint for electrically conductive connection of a preferably multi-core cable to an electrical device, or for electrically conductive connection of two preferably multi-core cables, with a cable terminal component and with a device terminal component or with the first cable joint component and a second cable joint component. In particular, the cable terminal component and the first cable joint component or the device terminal component or the second cable joint component include a union nut, a wire receiving and guiding part which has a plurality of wire guide channels, a clamping and terminal unit which is provided with insulation piercing connecting devices and with terminal elements, and a sleeve-like terminal body or connecting body which is provided with an outside thread which corresponds to the inside thread of the union nut, the wire ends which are to be squeezed by the insulation piercing connecting devices or which are to make contact with the insulation piercing connecting devices and the assigned insulation piercing connecting devices each running at an angle of less than 180xc2x0 and the insulation piercing connecting devices cutting through the wire insulation of the wire ends and making contact with the conductors when the union nut is screwed onto the terminal body or the connecting body or when the terminal body or the connecting body is screwed into the union nut.
2. Description of Related Art
First of all, the meaning to be given to certain terms used in the following description are to have the following meanings:
a) The term cable stands for an electrical line which has at least one wire, but generally several wires, the cable being a multi-core cable if there are several wires, the totality of which is surrounded by electrical insulation; and
b) The wires of a cable mean an electrical conductor with wire insulation thereon.
It was also stated initially that the cable terminal is intended for electrically conductive connection of a cable to an electrical device. Here, an electrical device should be understood quite generally; in particular, the expression electrical device will also include electrical components, means and devices.
In terms of its basic structure, the cable terminal or joint means under consideration consists of a cable terminal component and a device terminal component, or of a first cable joint component and a second cable joint component. If it is a cable terminal, this includes a cable terminal component and a device terminal component. If it is a cable terminal joint, this includes a first cable joint component and a second cable joint component.
It was further stated initially that for the cable terminal or joint under consideration, the cable terminal component or the first cable joint component or the device terminal component or the second cable joint component includes the following
a union nut,
a wire receiving and guide part,
a clamping and terminal unit which is provided with insulation piercing connecting
devices and with terminal elements and
a sleeve-shaped terminal or connection body which is provided with an outside thread
which corresponds to the inside thread of the union nut.
Thus, first of all, it is intentionally left open which of the individual parts, i.e., union nut, wire receiving and guide part, clamping and terminal unit and terminal or connecting body belong to the cable terminal component or the first cable joint component or to the device terminal component or the second cable joint component. In this respect it should be added:
that the union nut generally belongs to the cable terminal component or the first cable joint component, but also an embodiment is conceivable in which the union nut includes the device terminal component and the second cable joint component,
that the wire receiving and guide part belongs to the cable terminal component or the first cable joint component,
that the clamping and terminal unit belongs to the device terminal component or the second cable joint component and
that the terminal or connection body generally belongs to the device terminal component and the second cable joint component, but also an embodiment is conceivable in which the terminal or connection body belongs to the cable terminal component or the first cable joint component, specifically especially when the union nut belongs to the device terminal component or the second cable joint component as is described below as one possible embodiment.
It was further stated at the beginning that the wire ends which are to be squeezed by the insulation piercing connecting devices or which are to make contact with the insulation piercing connecting devices and the assigned insulation piercing connecting devices run at an angle of less than 180xc2x0. This means, first of all, only that the wire ends and the assigned insulation piercing connecting devices do not run parallel to one another, because then the insulation piercing connecting devices cannot act on the wire ends in the proper manner. The angle between the wire ends which are to be squeezed by the insulation piercing connecting devices and which are to make contact with the insulation piercing connecting devices and the assigned insulation piercing connecting devices can be both an acute and also a right angle; nor is an obtuse angle precluded. Accordingly, the wire guide channels, which hold the wire ends and which are provided in the wire receiving and guide part, are angled relative to the insertion direction of the cable. However, in order to ensure simple deflection of the wire ends during insertion, the angle should be less than 90xc2x0.
Finally, it was stated initially that when the union nut is screwed onto the terminal or connecting body or when the terminal or connecting body is screwed into the union nut, the insulation piercing connecting devices cut the wire insulation of the wire ends and make contact with the conductors. Screwing the union nut onto the terminal or connecting body, or screwing the terminal or connecting body into the union nut, leads to relative motion between the wire receiving and guide part and the clamping and terminal unit, and thus, to relative motion between the wire ends and the insulation piercing connecting devices. This relative motion leads to the insulation piercing connecting devices cutting through the wire insulation of the wire ends and then making contact with the conductors.
If, for better understanding, but in no way restrictively, the cable terminal or joint under consideration is reduced to a cable terminal with preferred assignment of the individual components to the cable terminal component, on the one hand, and the device terminal component on the other, it is therefore a cable terminal for electrically conductive connection of a preferably multi-core cable to an electrical device, with one cable terminal component and with one device terminal component, the cable terminal component including a union nut and a wire receiving and guide part and the device terminal component including a clamping and terminal unit which is provided with insulation piercing connecting devices and with terminal components, and a sleeve-shaped outside terminal body which is provided with an outside thread which corresponds to the inside thread of the union nut, the wire ends which are to be squeezed by the insulation piercing connecting devices or to make contact with the insulation piercing connecting devices and the assigned insulation piercing connecting devices running at an angle of less than 180xc2x0, and when the union nut is screwed onto the terminal body, the insulation piercing connecting devices cutting through the wire insulation of the wire ends and making contact with the conductors.
The aforementioned individual parts, the wire receiving and guide part, the clamping and terminal unit and the terminal or connecting body will now be explained. The following explanation of these individual parts relates to the above addressed cable terminal in which then the terminal or connecting body is called only the terminal body.
The wire receiving and guide part which belongs to the cable terminal component is conventionally provided on the cable side with a receiving or insertion opening for the totality of all wires or with a number of receiving or insertion openings which corresponds to the number of wires for the individual wires. Moreover, the wire receiving and guide part on the cable side is provided with the aforementioned wire guide channels. If the wire receiving and guide part on the cable side has only one receiving or insertion opening, this receiving or insertion opening then branches into the individual wire guide channels. However, on the cable side, a number of receiving or insertion openings which corresponds to the number of wires to be inserted is implemented, the individual receiving or insertion openings pass into the wire guide channels.
The wire guide channels which are implemented in the wire receiving and guide part are configured and guided with consideration of the geometry and the arrangement of the insulation piercing connecting devices of the clamping and terminal unit such that the wire ends which are to be squeezed by the insulation piercing connecting devices and which are to make contact with the insulation piercing connecting devices and the assigned insulation piercing connecting devices run at the desired angle, for example, at an acute angle or at a right angle.
The clamping and terminal unit which belongs to the device terminal component is provided on the side facing the wire receiving and guide part with insulation piercing connecting devices, on the other side with terminal components. They are metal parts which are generally made in one piece and which are configured on one side as insulation piercing connecting devices and on the other as terminal elements. The execution and configuration of the terminal components depends on which type of connection is desired or available for the internal wiring of the corresponding electrical device. In particular the terminal components can be made as flat connector, wire wrap or as solder terminal components.
As in the cable terminal under consideration, the union nut and the wire receiving and guide part represent the two important functioning elements of the cable terminal component, the sleeve-shaped terminal body which is provided with an outside thread which corresponds to the inside thread of the union nut and the clamping and terminal unit which is provided with insulation piercing connecting devices and with terminal components form the two important functional components of the device terminal component. When screwed together, i.e., when the union nut is screwed onto the terminal body, the union nut and the terminal body form a closed housing which holds and surrounds the inner function elements, specifically the wire receiving and guide part and the clamping and terminal unit.
German utility model 295 12 585, the essentially equivalent PCT patent disclosure document WO 97/06.580 and U.S. Pat. No. 5,989,056 which resulted therefrom, the company pamphlet from Phoenix Contact GmbH and Co xe2x80x9cQUICKON Q 1,5xe2x80x9d. . . , xe2x80x9cQuick connect technologyxe2x80x9d parts catalog 2 (March 1997) disclose another cable terminal or joint means.
In the known cable terminal or joint means the union nut and the wire receiving and guide part are two individual parts which are not connected to one another. Nor is a connection allowable because when the union nut is screwed onto the terminal or connecting body the wire receiving and guide part may not turn or cannot turn. The unimplemented connection has the consequence that, when the terminal or connection is unscrewed again, after unscrewing the union nut from the terminal or connecting body, first of all, the cable remains connected or joined, because the insulation piercing connecting devices of the clamping and terminal unit are still xe2x80x9cfixingxe2x80x9d the clamped conductors. Therefore, to unscrew the terminal or the connection again, after unscrewing the union nut from the terminal or connecting body, additional loosening of the conductors held by the insulation piercing connecting devices is required.
It is stated initially that the invention relates to a cable terminal or joint for electrically conductive connection of a cable to an electrical device or for electrically conductive connection of two cables. If it is a matter of connecting one cable to an electrical device, it is a cable terminal; if two cables are to be connected to one another, it is a cable joint. In the following, most of the time, the focus is on a cable terminal. But, nevertheless, a cable joint is always intended in the above explained sense.
The known cable terminal or joint means which was described above in particular and which represents a fundamentally new quick connection technology has already proven itself to be extraordinarily successful in practice. Nevertheless, in various respects, improvements, embodiments and developments are shown, which comprise the teaching of the invention.
The initially described cable terminal or joint by which the aforementioned problem is solved is characterized, first of all, essentially in that the wire receiving and guide part is axially fixed via at least one slotted, elastic locking ring in the union nut and that the wire receiving and guide part can be turned in the axially fixed position relative to the union nut. This has the major advantage that the relative axial motion between the union nut and the terminal or connecting body which accompanies the unscrewing of the union nut from the terminal or connecting body is also relative axial motion between the wire receiving and guide part and the terminal or connecting body which necessarily leads to the conductors which were clamped before in the insulation piercing connecting device coming free. If, in the cable terminal or joint in accordance with the invention, as is also accomplished in the prior art, the clamping and terminal unit is fixed in the terminal or connecting body, then, according to the invention, there is a cable terminal or joint which functionally is comprised of only two components, specifically the cable terminal component or the first cable joint component, on the one hand, and the device terminal component or the second cable joint component, on the other.
Basically, it is also possible to axially fix the wire receiving and guide part in the union nut via a catch connection. In any case, these catch connections with catch projections and catch grooves must often be produced very complexly by injection technology. Conversely, the locking ring is a simple component which can be designed according to the respective requirements and material.
The locking ring is held in the unjoined state of the wire receiving and guide part and the union nut, preferably, on the wire receiving and guide part, then, there being a projection in the union nut for fitting behind, or a corresponding groove for engaging, the locking ring. It goes without saying that it is, of course, basically also possible to hold the locking ring on the union nut and to provide the corresponding projections or a corresponding groove on the wire receiving and guide part.
For installing the locking ring, and thus, for holding on the respective component, preferably, on the wire receiving and guide part, at least one optionally peripheral axial holding projection is used. This prevents the locking ring from falling out of its installation position during assembly.
Furthermore, it is preferable that there be a locking means for the locking ring. These locking means are used especially to keep the locking ring, which is held on the wire receiving and guide part, in the desired position when the wire receiving and guide part and the union nut are joined. In particular, the locking means have at least one radial rib on the wire receiving and guide part and at least one groove on the locking ring for engaging the rib. It goes without saying that it is also fundamentally possible to provide other means or at least one rib on the locking ring and a corresponding groove on the wire receiving and guide part.
When the wire receiving and guide part and the union nut are joined, the locking ring, which has a cross section that is not larger than the diameter of the internal thread of the union nut, must be turned to its end by the internal thread of the union nut. Here, it assumes an axial slanted position according to the pitch of the thread. The locking means, therefore the ribs which fit into the groove, provide for the obliquely positioned locking ring to be entrained during turning in.
In one especially preferred embodiment of this invention, on the end face on the terminal or connecting body, there is a projection which, in the assembled state of the cable terminal or joint, fits into the slot of the locking ring so that by further screwing of the union nut onto the terminal or connecting body, the projection in the peripheral or tangential direction acts on the clamp ring and widens it. This ultimately yields protection for the locking ring since its outside strikes the inside surface of the union nut after a corresponding widening and then can no longer be widened.
In one preferred development, on the outer peripheral surface of the locking ring and/or on one inner peripheral surface of the union nut, there are grooves, teeth or the like in the area of the locking ring. After the corresponding widening, the aforementioned surfaces interact with one another; this leads to the so-called ratchet effect which, in turn, leads to higher expenditure of force due to the higher torque during attachment and also when the union nut is unscrewed. This ultimately protects the union nut from coming unscrewed.
In the following, one embodiment of this invention is explained using the drawings.